Well drill



Juiy 10, 1923.

- F. L.. GlLMAN ET AL WELL DRILL Filed July 22 1921 Ema/fl. Gila/mi? Jase 75 Z90;

Patented July 10, 1923.

" STATS P T N F I I E o FRANK L. GILM'AN AND JOSEPH R. WILSON, OF LOS ANGELES, CALIFORNIA, ASSIGNORS OF ONE-FOURTH TO RENI S. BERRY, OF LOS ANGELES, CALIFORNIA; SAID WILSON ASSIGNOR 0F ONE-THIRD OF HIS RIGHT TO CASWELL C. MATLOCK, OF LOS AN- GELES, CALIFORNIA WELL DRILL.

Application filed July 22, 1921.

To all whom it may conoem:

Be it known that we, FRANK L. GILMAN and JosnPH R. WILSON, citizens of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in a Well Drill, of which the following is a specification.

This invention relates to a drill of the class employed in the sinking of deep wells, and particularly wells that are lined with casing, such as in oil wells and the like.

An object of this invention is to provide a drill of the above character which is adapted to be operated by air under pressure in effecting a cutting action, and in Which the air employed for operation of the drill may thereafter be used to aid in the removal of the dbris from the bore.

Another object 'is to provide an air operated drill embodying a plurality of drills carried by a head adapted to be lowered into the bore as the drills advance, in which the operation of the drills is controlled by moving them in or out of their drilling position at the bottom of the bore.

A further object is to proyi'de an effective means for'imparting reciprocal movement to a drill by fluid pressure.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the 1nvention consists of the parts and the construction and arrangement of parts hereinafter specified and claimed, and set forth in the accompanying drawings, in which Figure 1 is a view in side elevation partly in transverse section and with parts broken away, showingthe application of the invention.

Figure 2 isa detail transverse section of the air cylinder.

Figure 3 is an end view of the drill as seen when projecting beyond the end of the well casing.

More specifically, 5 indicates a c lindrical head embodying a tubular ousing adapted to be lowered into a well casing 6 and having an external diameter slightly less than the internal diameter of the cas ing, so as to be guided by the casing and et have free movement therein. Secured 1n the head are spaced walls 7 and 8 Serial No. 486,675.

through which a pipe 9 slidably extends; the pipe being splined to the wall 8 by longitudinally extending keys 10, so that on rotation of the pipe the head will turn therewith. The wall 8 is spaced from I the lower end of the housing and pivotally connected to its underside by pivots 11 is a plurality of dependent cylinders 12, here shown as two in number, and each of which is fitted with a piston 13 carrylng a shank 14 projecting through a wall 15 on the outer end of the cylinder and having a suitable cutting tool 16 on its outer end. Each cylinder is designed to normally depend vertically on its pivotal mounting by gravity when the head is in its lowermost position on the pipe with the wall 8 seating on a collar 17 provided on the lower end of the pipe, and is intended to be swung outwardly into an inclined position on advancing the pipe relative to thehead, whereby the tool 16 carried by the cylinder may be projected beyond the plane of the exterior of the casing 6 so that on operation of the cutting tools as later described they will cut a hole of a diameter greater than that of the casing, or. in other words effect an underreaming action. For this purpose the side of the cylinder adjacent the pipe is formed with a longitudinal rib 18 of gradually increasing thickness progressing from the upper end of the cylinder. toward its lower end and forming an inclined face, which is adapted to be acted on by the collar 17 as the pipe is moved downwardly, in such manner as to move the lower end portion of the cylinder outwardly and cause it to abut against the margin of the lower end of thehousing in an outwardly inclined position, as shown in Figure 1 and thereby project the tool into its underreaming position.

Means are provided for automatically controlling the introduction of air under pressure into theupper end of the cylinder, operable by swinging movement of the -cylinder on its pivota mounting. For this purpose the upper end of the cylinder is formed with an arcuate or semi-circular ortion 19, which seats in a concave cavity 50, formed on the underside of the wall 8, and the walls of which conform to the arcuate end of the cylinder; the adjacent curved surfaces of the end of the cylinder 1 and the bottom wall of the cavity being formed concentric with the axis of the pivot 11, so that these surfaces will be 1n plates 24 and 25, rigidly mounted on the ipe 9, and havingoppositely beveled outer aces, engaging correspondingly tapered faces on a stationary ring 26; a space being formed between the plates 24 and on thering 26, to which air under pressure is delivered through a pipe 27, leading from any suitable source of air supply and openin through the ring 26. The assage 21 opens to the bottom wall of the cavity 20 and is normally closed by the arcuate wall of the end 19 of the cylinder, when the latter is in its dependent vertical position, as shown in Figure 2. I

The upper end of the cylinder is formed with a port.28, leading from the arcuate end face to a bore 29, opening to the interior of the cylinder; the outer end of the port 28 being so positioned as to register with the to admit air under passage 21, When the cylinder'is disposed in its inclined position, as shown in Figure l,

ressure to the cylinder, but which port will be moved out of register with the passage 21, so that the latter will be closed, when .the cylinder is in its vertical position.

Means are provided whereby the admission of air under pressure through the interior of the cylinder will automatically effect reciprocal movements of the piston 13, and while we may employ any well known construction for this. purpose, as is common in compressed air operated tools, we prefer to use the construction shown in Figure 2, which will now be described:

Extending'through the piston 13 and loosely mounted therein, is an open ended tube 30, the upper end portion of which extends into the bore 29, and has a longitudinal depression or channel .31, formed in one side thereof, adapted tobe placed in, communication with the portf28; the bore 29 extending beyond the port 28, so that when the tube 30 is disposed in its uppermost position, as shown in Figure 2, the upper end of the tube will be located above "the port 28.

Formed on the tube '30'is a pair of spaced flanges or collars 32 and 33, spaced apart a: greater distance than the width of the piston 13,. so that the latter may have movement relative to the tube, aswill presently be described.

The upper end portion of the tube 30 has such frictional engagement with the bore 29 as to oppoa free movement of the tube, so

that the latter will remain stationary, during movement of the piston 13, until it is actuated by thepiston. A second tube 34 is provided for the purpose, of exhaust, which tube extends through the end wall 15 of the cylinder in free slidable connection therewith and projects upwardly through the piston 13, in tight frictional engagement with the latter; the lower end of the exhaust tube opening exteriorly of the cylinder, This tube is closed at its upper end and is formed with a pair of spaced ports 35 and 36, separated a distance slightly less than the width of the piston 30, and which portsare designed tobe opened alternately above and below the iston to exhaust the opposite.

ends of the cy inder on the exhaust tube being actuated by the piston, as will presently appear.

' Assuming the well having been partly sunk and the casing 6 lowered in place, the drill is operated as follows: To lower the head into the casing it is suspended on the pipe 9 with the wall 8 seating on the collar 17 and with the cylinders depending vertically, so as to close the air supply to the cylinders. When the head has been lowered into the Well to bring the drills intocontact with the bottom of the bore downward movement of the pipe 9 is continued to cause the collar'17 to press the cylinders outwardly, and thereby incline the drills outwardly whereby the cutting tools 16 will project in part beyond the plane of the casing so that on operation of the drills they will cut a bore sufliciently larger in diameter than the casing to permit the latter to move downwardly in the bore. The outward movement of the cylinders also acts to open the ports 28 to the passages 21 and thereby admit air under pressure to the cylinders and efiect operation of the drills in the following manner.

Assuming the piston to be in its uppermost position with the tube 30 in its uppermost position and the tube 34 disposed with the port 36'opento the cylinder beneath the piston 13, air will then flow into the cylinder above-the piston through the channel 31, which is of'such length that when the upper end thereof is in-communication with the port 28 the lower portion thereof will be open to the cylinder. The pressure of the air entering the cylinder will cause the iston to move downwardly and effect a b 0w of the drill; On downward movement of the piston, the tube 34 will be carried therewith and the port 36 remaining open will afford a means for the discharge of the air 3 'tube 34 has come to rest and will advance on the tube 34, so as to close port 36 and open port 35 above the piston.

During the portion of the down stroke of the piston occurring before closing of the port 36 the tube 30 will remain stationary, but when the piston nears the end of its down stroke it will move against the collar 33 on tube 30 and cause the tube tomove with the piston such distance that the upper end of the tube will be positioned below the port 28, so that .air under pressure delivered to the port will then pass through tube 30- and enter the lower portion of the cylinder beneath the piston. Port 36 then being closed the air under pressure will act to retract the piston; the air above the piston then venting through the open port 35.

The tube 34: moves upward with the piston until a collar 38 thereon strikes the lower end of the cylinder to limit the upward movement of the tube 34, so that continued movement of the piston will close port 35 and open port 36. The piston on approaching the termination of its up stroke abuts the collar 32 on tube 30 and restores the latter to its uppermost position; the tube remaining stationary during movement of the piston between the collars 32 and 33.

When it is desired to remove the drill i from the casing, the pipe 9 is drawn upwardly to move the collar 17 thereon into engagement with the lower face of the wall 8-, so that the head will then be carried on the collar. Continued movement of the pipe will lift the head so that the cylinders will swing by gravity to a vertical position, and thereby cut off the air supply to the cylinders andat the same time retract the drills relative to each other, so that they ma be drawn upward through the casing,

n effecting the drilling operation, the pipe 9 is rotatedto efl'ect, rotation of the head, so that the drills will work throughout.. the bottom of the bore being drilled. Any suitable mechanism may be employed for this purpose, such as is commonly used in well drilling operations.

In drilling the well, the drills cut a bore slightly larger than the outside diameter of the well casing 6 and in sinking the casing water is forced downwardly around the easing, so as to enter the lower end of the casing and pass upwardly through the pipe 9. The air exhausting from the cylinders is discharged into the body of water below the head and caused to pass upwardly through the pipe 9, and in so doing assist in maintaining an upward flow of water through the pipe 9 and thereby aid in discharging the materials removed by the drill.

We claim:

1. In a drill, a head, a plurality of cylinders pivoted on said head, pistons in said said cylinders for admitting air under pressure to said cylinders, and means for automatically effecting reciprocation of said pistons on delivery of air to the cylinders.

2. In a drill, a head, a plurality of cylinders pivoted on said head, pistons in said cylinders, drills carried by said pistons, air feed passages in said head, an air inlet port in said cylinders; said passages and ports arranged to be disposed in and out of communication with each other on oscillation of said cylinders, and means for automatically effecting reciprocation of said pistons on delivery of air to the cylinders.

3. In a drill, a head, a cylinder pivoted on said head having a segmental end fittin in a corresponding cavity in the hea formed concentric with the pivotal mounting of the cylinder, an air feed passage in said head leading to the cavity, an air inlet port in the segmental end of the cylinder; said passage and port adapted to move in and out of communication with each other on oscillation of the cylinder, a piston in said cylinder, a drill carried by said piston, and means for automatically efi'ecting reciprocation of said piston on admission of air under pressure to said cylinder.

4. In a drill, a head, a cylinder pivoted thereon, a pipe on which said'head is slidable, means operable by reciprocal movement of the head relative to the pipe for oscillating the cylinder, means controlled by oscillation of the cylinder for admitting air under pressure to the latter, a drill, and a piston on which said drill is carried mounted in the cylinder and adapted to be reciprocated by the delivery of air. under pressure to the cylinder.

5. In a drill, a head, a cylinder pivoted thereon, a pipe on which said head is slidable, means operable by movement of the head relative to the pipe for oscillating the cylinder, means controlled by oscillation of the cylinder for admitting air under 'pressure to the latter, a drill, and a piston on which said drill is carried mounted in the cylinder and adapted to be reciprocated by the delivery. of air under pressure to the cylinder.

6. In a drill, a drill rod, a. cylinder pivotally carried thereon normally depending substantially vertical and adapted to be thereon and normally depending verticallytherefrom, a support on which said head is slidably carried, means operable by move-' ment of the head relative to the support for oscillating the cylinder whereby the cylin- 5 der may be swung to an outwardly inclined position, means for admitting air under pressnre to the cylinder, a piston mounted in the cylinder and adapted to be reciprocated by delivery of airunder pressure to the cylinder, and a drill carried by said pis- 10 FRANK L. GILMAN. JOSEPH R. WILSON 

